An organic electroluminescent device is a light emitting device which is a spontaneous emission type and is expected as a light emitting device for display or lighting. A display unit using an electroluminescent light emitting device has so far been researched in various cases because of possibility of small power consumption and reduction in a thickness. Further, an organic electroluminescent device comprising organic materials has so far been actively investigated since reduction in a weight and increase in a size are easy. In particular, developments of organic materials having light emitting characteristics including a blue color which is one of three primary colors and developments of organic materials endowed with charge transport ability (having possibility of being derived into semiconductors and superconductors) of holes and electrons have so far been actively researched regardless of high molecular compounds and low molecular compounds.
An organic electroluminescent device has a structure comprising a pair of electrodes comprising an anode and a cathode and a single layer or plural layers which are disposed between a pair of the electrodes and which contain organic compounds. The layer containing organic compounds includes an emission layer and a charge transport/injection layer which transports or injects charges such as a hole and an electron, and various organic materials have been developed as the organic compounds (for example, International Publication No. 2004/061047 pamphlet and International Publication No. 2004/061048 pamphlet (JP H18-512395 (through PCT) A/2006): refer to a patent document 1 and a patent document 2). However, only high molecular compounds of benzofluorene are disclosed in the examples of the patent documents. Also, International Publication No. 2003/051092 pamphlet (JP H17-513713 (through PCT) A/2005), for example, describes dibenzofluorene compounds having amino substituted with aryls (refer to a patent document 3). However, the document describes only structural formulas thereof, and does not describe the specific characteristics thereof.    Patent document 1: International Publication No. 2004/061047 pamphlet    Patent document 2: International Publication No. 2004/061048 pamphlet (JP H18-512395 (through PCT) A/2006)    Patent document 3: International Publication No. 2003/051092 pamphlet (JP H17-513713 (through PCT) A/2005)
However, even if the organic materials described above are used, organic electroluminescent devices having satisfactory performances in terms of heat resistance, luminous efficiency, current efficiency, device life and external quantum efficiency have not yet been obtained. Under the situation described above, desired to be developed is an organic electroluminescent device having further better performances in terms of heat resistance, luminous efficiency, current efficiency, device life and external quantum efficiency, that is, a compound which can provide the device.
Further, in order to meet commercial production of light emitting devices, desired are organic materials which are more easily synthesized and organic materials which can accept any processing conditions in applying to devices. For example, organic materials having an excellent solubility in a solvent are relatively easily synthesized and have the merit that they are not limited to a vapor deposition method in forming layers.